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In logic and mathematics, or, also known as logical disjunction or inclusive disjunction, is a logical operator that results in true whenever one or more of its operands are true. E.g. in this context, "A or B" is true if A is true, or if B is true, or if both A and B are true. In grammar, or is a coordinating conjunction. In ordinary language "or" sometimes has the meaning of exclusive disjunction.
Contents
Notation
Or is usually expressed with an infix operator. In mathematics and logic, it is usually ∨; in electronics, +; and in programming languages,  or or. Some programming languages have a related control structure, the shortcircuit or, written , or else, etc.
Definition
Logical disjunction is an operation on two logical values, typically the values of two propositions, that produces a value of false if and only if both of its operands are false. More generally a disjunction is a logical formula that can have one or more literals separated only by ORs. A single literal is often considered to be a degenerate disjunction.
Truth table
The truth table of :
Properties
The following properties apply to disjunction:
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